Caption: Supply boat bringing food to a fattening pen for Atlantic bluefin tuna (Thunnus thynnus). Bluefin tuna are highly prized as a food fish, and commercial aquaculture is aimed at ensuring a regular supply. Overfishing and unsustainable farming techniques have led to a dramatic decline in wild populations of as much as 90% in the last 40 years, and it is classified as an endangered species by the IUCN. Filmed off the coast of Barbate, Andalusia, Spain.